The present invention relates to an engineered composite system, system component compositions and methods of use, and in particular to a system employing a thermosetting asphalt extended cross-linked hybrid basecoat for resting on a porous substrate, and for receiving a thermoplastic top coating.
A number of coating materials have been proposed for thermal field applied applications, particularly flame-sprayed coatings. One problem with these types of field-applied coatings is that the substrate may be porous, e.g., wood or concrete, and is subject to off-gassing or thermal decomposition. Consequently, it is very difficult to coat these types of materials.
Accordingly, there exists a need for improved coating systems and compositions to solve the problem of coating porous substrates.
The present invention solves this need by providing a field applied coating system that is ideally adapted for porous substrates.
It is a first object of the present invention to provide an improved field applied engineered composite system coating.
Another object of the invention is a field applied and/or shop applied, engineered composite system comprising: 1) an asphalt extended, chemically cross linkedxe2x80x94urethane/epoxy hybrid basecoat, 2) an alcohol/silane primer, 3) a thermoplastic powder coating topcoat, 4) a optional fabric or fiber reinforcement layer, and the system components of the basecoat, the topcoat, and the primer.
Other objects and advantages of the present invention will become apparent as a description thereof proceeds.
In satisfaction of the foregoing objects and advantages, the present invention provides a coating system that comprises a basecoat of an thermosetting asphalt extended, chemically cross linkedxe2x80x94urethane/epoxy hybrid basecoat resting on a substrate, preferably a porous substrate such as concrete or wood that off-gas when coated with a thermoplastic material; and a thermoplastic powder coating topcoat overlying at least the base coat. An alcohol-silane primer can be on the substrate and surrounding at least a portion of the basecoat while leaving a portion of the substrate exposed, the topcoat overlying both the primer and the portion of exposed substrate.
The system can further comprise a reinforcing layer disposed between the basecoat and the topcoat, and the reinforcing layer can be one of a metallic or non-metallic fiber such as glass, a natural fiber such as cotton, a polymeric fiber, a carbon fiber, or combinations thereof.
The thermosetting basecoat composition comprises, in weight percent based on final formulation:
between 10 and 90%, preferably 20 and 70, and most preferably 30 and 60% of a petroleum asphalt;
between 10 and 90%, preferably 20 and 70, and most preferably 30 and 60% of a hydroxy-terminated homopolymer;
between 0.1 and 30%, preferably 3 and 25, and most preferably 5 and 15% of a functional epoxy reactive diluent for reducing the viscosity of the composition;
up to 5%, preferably 0.2 and 3%, and most preferably 0.3 and 1.0% of a surfactant for improving surface imperfections;
up to 5%, preferably 0.2 and 3%, and most preferably 0.3 and 1.0% of an anti-oxidant; and
up to 25%, preferably 0.1 and 10%, and most preferably 0.5 and 2.0% of an thickening agent.
The basecoat can also comprise an effective amount of a hardener to cross link with the hydroxyl functional polybutadiene and reactive diluent components and active hydrogen contained in the asphalt, wherein the hardener is preferably an isocyanate type hardener, but can be diamine or an equivalent hardener.
The basecoat composition can optionally including one or more of a catalyst in a range between 0.0001 and 5%, preferably 0.005 and 2%, and most preferably 0.1 and 2.0%, polyols for higher strength, other fillers for viscosity adjustment between 0.1 and 75%, functional silanes at 0.001 to 10%, thermal conductivity agents between 0.1 and 75% of the formulation such as zinc oxide for resiliency and conductivity, other fillers such as hollow and/or solid glass spheres (0.001 to 5%), drying agents ranging up to 20 gram/gram of water present, flame retardants in amounts between 0.1 and 60%, corrosion inhibitors ranging from 0.1 and 50%, antistatic agents ranging from 0.1 to 50%, biostabilizers ranging from 0.1 to 10%, chemical blowing agents ranging from 0.1 to 10%, scent additives ranging from 0.1 to 25%, bittering agents ranging from 0.1 to 25%, pigments ranging from 0.1 to 40%, fluorescent whiting agents, ranging from 0.1 to 10%, lubricants, UV stabilizers ranging from 0.001% to 50%, powdered (xe2x88x9220 to xe2x88x921250 mesh size) thermoplastic materials and optionally 0.001% to 50%, powdered thermoplastic with incorporation of one or more of the following: fillers, thermal conductivity agents, flame retardants, corrosion inhibiters, antistatic agents, biostabilizers, chemical blowing agents, scent additives, bittering agents and pepper, pigments/effects, fluorescent whiting agents, lubricants, plasticizers, etc. (xe2x88x9220 to xe2x88x921250 mesh size), and plasticizers each ranging from 0.1 to 25%.
A topcoat thermoplastic composition comprises, in weight percent, based on final formulation:
between 10 and 90%, preferably 20 and 70, and most preferably 30 and 60% of a modified ethylene terpolymer with a temperature stable ester and high acidic functionality;
between 5 and 95, preferably 20 and 70, and most preferably 30 and 60% of a polyethylene/methacrylic acid copolymer;
between 5 and 95, preferably 5 and 70, and most preferably 7.5 and 20% of a polyethylene/methacrylic acid copolymer ionomer;
up to 50% of a coloring pigment;
up to 5% of an anti-oxidant;
up to 5% of an ultraviolet stabilizer;
up to 5%, preferably 0.2 and 3%, and most preferably 0.3 and 1.0% of a surfactant for improving surface imperfections; and
up to 25%, preferably 0.1 and 10%, and most preferably 0.5 and 2.0% of a thickening agent.
The topcoat composition can optionally contain one or more of other fillers for viscosity adjustment between 0.1 and 75%, thermal conductivity agents between 0.1 and 75% of the formulation such as zinc oxide for resiliency and conductivity, drying agents ranging up to 20 gram/gram of water present, flame retardants in amounts between 0.1 and 60%, corrosion inhibitors ranging from 0.1 and 50%, antistatic agents ranging from 0.1 to 50%, biostabilizers ranging from 0.1 to 10%, chemical blowing agents ranging from 0.1 to 10%, scent additives ranging from 0.1 to 25%, bittering agents ranging from 0.1 to 25%, pigments ranging from 0.1 to 40%, fluorescent whiting agents, raging from 0.1 to 10%, and lubricants, and plasticizers each ranging from 0.1 to 25%.
A primer composition for use with the composite coating system employing a thermosetting resin basecoat and a heat-applied thermoplastic resin overlying the basecoat consists essentially, in weight percent, of between zero and up to 10% of a silane, a solvent ranging between 80 and 95%, and the balance water. The silane can be one of: an ionic and anionic silane; a methanol, organic phosphonium chloride salt and silane monomer; or any other silane having an active hydrogen.
The method also entails coating at least a portion of a substrate by first mixing the basecoat composition with or without the optional ingredients noted above with an isocyanate hardener to form a thermosetting mixture. The basecoat is applied as a liquid to a substrate, preferably a porous substrate and the basecoat is allowed to chemically crosslink to form a heat dampening basecoat. Then, the topcoat of claims with or without the optional ingredients is thermally applied onto the heat dampening basecoat to a given thickness to coat the substrate. A portion of the substrate can be masked prior to basecoat application. Preferably, the substrate is masked twice, the second mask covering both a first mask and a part of the substrate, the second mask removed after basecoat application to expose the part of the substrate for topcoat application.
One or more of the resin components of the topcoat composition with or without the optional ingredients can be substituted with one or more of the polymers as detailed below.
The topcoat composition can be further modified with the incorporation of one or more of other fillers for viscosity adjustment between 0.1 and 75%, thermal conductivity agents between 0.1 and 75% of the formulation such as zinc oxide for resiliency and conductivity, drying agents ranging up to 20 gram/gram of water present, flame retardants in amounts between 0.1 and 60%, corrosion inhibitors ranging from 0.1 and 50%, antistatic agents ranging from 0.1 to 50%, biostabilizers ranging from 0.1 to 10%, chemical blowing agents ranging from 0.1 to 10%, scent additives ranging from 0.1 to 25%, bittering agents ranging from 0.1 to 25%, pigments ranging from 0.1 to 40%, fluorescent whiting agents, ranging from 0.1 to 10%, and lubricants, and plasticizers each ranging from 0.1 to 25%.
The invention also entails a method of coating at least a portion of a substrate by first mixing the basecoat composition as defined above with an isocyanate hardener to form a thermosetting mixture, and storing the mixture in the absence of atmospheric moisture. Then, the mixture is applied to a substrate, preferably a porous substrate and the basecoat is allowed to chemically crosslink to form a heat dampening basecoat. Then, the topcoat as noted above is thermally applied onto the heat dampening basecoat to a given thickness to coat the substrate. In this method, a reinforcing material can be applied on the basecoat and before the topcoat.